SAPPORO, Japan (Reuters) - Indigenous communities from around the world urged G8 rich nations on Friday to help them participate in global climate change talks, saying they contributed least to but are most affected by global warming.

Clad in colorful traditional robes, 26 representatives from countries including the United States, Canada, and Japan, along with some 400 students, activists, and academics, met on Japan's northern island of Hokkaido.

The island is the venue of the July 7-9 Group of Eight summit and home to the indigenous Ainu ethnic group.

At the meeting, members of indigenous communities blamed the market-oriented economic model of the G8 nations as the main cause for climate change, a food crisis, and high oil prices. These are issues high on the discussion agenda at the G8 summit.

"As we all know, the G8 is composed of the most powerful and richest governments in the world. The G8 is the one which makes decisions ... that have direct impact on us," said Victoria Tauli-Corpuz, Chair of the U.N. Permanent Forum on Indigenous Issues.

"As far as I am concerned ... we have seen that many of these problems are actually caused by the G8 themselves," added Tauli-Corpuz, also a representative of the Igorot people of the Philippines.

A declaration issued at the meeting's end said the G8 leaders should pave the way for indigenous people to be included in global climate change talks led by the United Nations.

"Indigenous peoples need to be included in all levels of climate change negotiations, because they are the most affected, but also because they have the most to contribute," said Ben Powless, a Mohawk from Canada.

Many sang and chanted prayers in their indigenous languages at the meeting.

The United Nations has estimated 370 million indigenous people were already exposed on the front line of climate change to more frequent floods, droughts, desertification, disease and rising seas.

At the meeting, indigenous communities highlighted the troubles they were also facing from the effects of measures intended to mitigate climate change.

For example, Tauli-Corpuz said people had been displaced when biofuel plantations were expanded in the Philippines and when forests were used as carbon sinks in Uganda.

"We are really pleading to the governments to ensure that in the process of undertaking programmes, they will not further (marginalize) and violate the basic rights of the indigenous peoples," she told Reuters in an interview.

In their declaration, representatives also called for the governments of Canada, the United States and Russia to adopt the U.N. Declaration on the Rights of Indigenous Peoples.

The United States and Canada voted against the non-binding declaration while Russia abstained. Australia and New Zealand also voted against it, but it was passed overwhelmingly in the General Assembly in September 2007.

Representatives welcomed the move by the Japanese government last month to recognize Ainu as indigenous people, but called for an official apology for mistreatment of the Ainu and concrete steps, as well as including more Ainu representatives in an experts' committee.

Only one Ainu was named to the eight-member committee formed by Japan's government this month.

The declaration from the meeting will be handed over on Friday to Japanese lawmakers, who will pass it to Japanese Prime Minister Yasuo Fukuda before the summit, meeting organizers said.